This is an ABC news special report. Good afternoon I'm Bill -- in New York we're joining -- this afternoon with breaking developments in the massive manhunt for a suspected triple murderer. In Southern California Christopher -- -- is the former police officer. Fired by LAPD some years ago and now suspected of a revenge fueled killing spree. Targeting a law enforcement and their families is online manifesto vowed to bring warfare. On LAPD -- in the six days since his first suspected ambush the city the whole. Area of Southern California has been on blue alert and right now -- in the last -- so there's been an amazing amount of police activity. Just south of big bear lake up in the San Bernardino national force it's about eighty miles east of Los Angeles. Dozens of officers responded to a cluster of cabins there in the snowy woods. Had this is an area where his truck was found burned out some days ago the search is gone all the way to the Mexican border but in recent days. It's come to this and we're piecing together very fluid reports coming from scanner traffic. Local reporters he Associated Press. And what led us to and to this point is is still to be determined but as they bring in Pierre Thomas or chief law and justice correspondent. You have reporting that that says it would started with a home invasion -- That's right bill I was senior law enforcement official telling me -- apparently a suspect matching the order's description. All the water more people hostage in their -- Didn't escape -- -- -- vehicle. My source says that police have made contact with. We suspect there's been exchange of gunfire quite this sort. And then a massive response is under way he described the situation is extremely who. And Cecilia Vega one of our team in Los Angeles has been watching this unfold Cecilia you heard. Actual gun fire the gun battle ongoing local it. Bill this this footage here are being reported by local LA stations is remarkable life seems to be a reporter from one of the stations here is is near where this battle is taking place -- what we're seeing on the ground in the air again this very rural area about ten miles or so away from big bear as you said -- donors. Car was found is. Teams of swat officers from around Los Angeles area with their rifles out they have been pointed now for twenty minutes at least maybe half an hour now. At this cabin where it's believed. The suspect the Warner is is is there are -- it's an exceptionally tense situation we're hearing officers. Screaming and yelling on -- live television again gunfire going off as these reporters are filing their reports. When reporter says he hasn't seen these officers put their rifles down at the time that this has been going on again for about half an hour -- -- an exceptionally tense situation bill. That we're monitoring here from Los Angeles today. Cecilia I don't believe we do have a -- a tape just to give a sense of what you were just describing. Of that situation can we hear the. Simple but -- yeah. -- -- you get a sense there we've heard reports that automatic weapons were involved certainly sounded like it from just that snippet there as well. Just about everyone with a badge in Southern California has been looking for Christopher -- for six days now and this must be. Some encouraging news for the families of the -- wives and children. That's -- needed protection recent days but we will keep a close eye on this. -- I'm just getting word that's that perhaps -- Warner's. Injury rates is rising KAVCR station Los Angeles reporting that two officers. Will be airlifted from the scene after one of these shoot -- we've heard reports of more than one justice since lunchtime in Southern California. And this coming after three in the horrific killings thus far but several ambushes as well. In that sense fluid situation as we mentioned we'll keep our eyes on at the very latest at abcnews.com. And the full story. On world news with Diane Sawyer. Good afternoon. This -- business.

This transcript has been automatically generated and may not be 100% accurate.

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